Fig. 3

Cholesterol and lipid droplet accumulation are increased in astrocytes isolated from APOE-deficient iPSC-derived cerebral organoids. a Astrocytes were isolated from the cerebral organoids through FACS using the cell surface marker GLAST1. Representative fluorescence microscopy images of the isolated astrocytes stained with antibodies against S100β and GFAP. Scale bar: 20 μm. b SFRP1 mRNA expression in the isolated astrocytes was quantified by RT-qPCR (n = 6 wells/genotype). c–f Protein levels of SFRP1 (d), β-catenin (e) and Wnt7b (f) in the isolated astrocytes were quantified by Western blotting (n = 6 wells/genotype). g–i Protein levels of ABCA1 (h) and ABCG1 (i) in the isolated astrocytes were quantified by Western blotting (n = 4 wells/genotype). j The isolated astrocytes were plated on coverslips and stained with Filipin III for cholesterol. Filipin III intensities were quantified in 3 fields of each coverslip and averaged (n = 4 coverslips/genotype), Scale bars, 20 μm. k The isolated astrocytes were plated on coverslips and stained with LipidTox for lipid droplets. The lipid droplet number and size per cell were quantified in 3 fields of each coverslip and averaged (n = 5 coverslips/genotype). Scale bars: 10 μm. Experiments were repeated in two independently differentiated batches. All data are expressed as mean ± SEM. Student’s t tests were performed to determine statistical significance. **p < 0.01, **** p < 0.0001. For raw data see Additional file 1: Figs. S9 and S10